Automatic shutoff assembly for a water closet

ABSTRACT

An automatic shutoff valve and sensor assembly is disclosed to control water supply to a toilet. There is a housing mountable upstream of the toilet and downstream of the room water supply. There is also a shutoff valve, an automated sensor, and a microcontroller in the housing. The sensor is suitable to detect when a potential user is adjacent the water closet. If it detects a user, the sensor can send an output signal that ultimately leads to the opening of the shut-off valve. The shutoff valve then later automatically re-closes when users aren&#39;t present. A manual override can be incorporated in the housing as well. This reduces the potential for water leaks and water waste from the toilet.

CROSS-REFERENCE TO RELATED APPLICATION

Not applicable.

STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION

The present invention relates to automatic shutoff assemblies for controlling supply water to toilets, particularly where the assemblies activate and de-activate water supply shutoffs in response to the presence or absence of potential users.

Water supplies for toilets are often controlled by a manually controllable shutoff valve located on a wall near the toilets. However, because a typical home or other building can have many such shutoff valves, consumers will often not bother to use them unless they are leaving for a very extended period (e.g. closing up a cottage over the winter), or unless they are performing specific maintenance on a particular fixture.

Unfortunately, sometimes toilets develop leaks when a homeowner is away for a shorter period. For example, if a toilet tank developed a crack due to a freezing problem in the home, resulting in a leak, water might continue to flow to the tank, and thus the leakage might continue for a very long period, before the homeowner returns home and discovers the problem. Alternatively, a flapper outlet valve from a toilet tank might not properly seal, allowing continued waste of water until the homeowner returns.

In the plumbing field there have been developed a variety of motion and/or proximity sensors coupled to the outlet valve of plumbing fixtures to provide automatic (touchless) control of outlet flow. These include passive infrared sensors that sense body heat, and microwave, ultrasonic, radio wave, or other sensors that send out pulses and measure the reflection off objects.

As one example, faucet output water has been turned on or off at a sink in response to sensing the presence or absence of a hand beneath a faucet. As another example, toilets and urinals have been flushed automatically after sensing a user and thereafter sensing that the user has moved away from the area. See e.g. U.S. Pat. Nos. 3,585,652, 4,915,347, 6,568,655, 6,964,405, 6,996,863 and 7,014,166. Such automated control systems often involved use of solenoid valves under the control of a microcontroller. See e.g. U.S. Pat. No. 6,382,252.

However, these devices control outflow from a plumbing fixture, rather than controlling inflow to a tank associated with the fixture. Hence, they don't seek to address problems involving leaks at a toilet tank.

In other work various leak/overflow detectors have been developed for use with toilets. U.S. Pat. No. 6,367,096 uses a water level sensor mounted in the bowl to detect an overflow condition and a separate sensor mounted in the tank to detect a leak condition. Upon detecting either such condition, a microprocessor-operated controller sends a signal to close an automated shutoff valve to stop the flow of water to the tank. However, the presence of sensor assemblies in either the tank or the bowl create hygienic concerns, and the sensors may degrade due to their being in a water and/or cleaning liquid environment.

U.S. Pat. No. 6,934,977 provides another leak detector in a toilet tank that is associated with a shutoff valve. This construction is somewhat costly due to the need to have features that are water resistant, and presents an undesirable aesthetic appearance due to exposed wiring. Also, if the sensor quits working, it may be difficult to fix the problem without replacing the entire toilet.

U.S. Pat. No. 5,918,617 electrically couples a proximity sensor to the water supply shutoff valve of a toilet. When the proximity detector senses the presence of a user of the toilet, the shutoff valve is opened, thereby providing a water supply. After sensing the absence of a user for a pre-determined time, the shutoff valve is automatically closed.

While this system does automatically protect against continuous leakage from the toilet tank, it has it had several disadvantages. For example, it requires multiple skill sets for installation (e.g. a skilled plumber to attach the shutoff valve, and a skilled electrician to mount a proximity sensor through a wall). Further, exposed wiring had an undesirable aesthetic appearance.

U.S. Pat. No. 6,691,724 disclosed motion sensors that would shut off all household water supply if there was a lack of movement in the home for a specified period. Unfortunately, this could also shut off water from devices where a shutoff was not desired. More importantly, it was not a system that could be easily retrofit to existing homes.

In sum, prior art devices were deficient in not mounting the sensor and shutoff valves so that they appear to homeowners to be part of the normal toilet construction. Further, prior art devices often require exposed wiring and present significant installation costs and difficulties.

Hence, a need remains for improved automated shutoff valves that can be used with toilets, particularly in retrofit applications.

SUMMARY OF THE INVENTION

The present invention provides an automatic shutoff valve and sensor assembly suitable for use with a water closet positioned. The assembly has a housing mountable upstream of the water closet in the room, the housing having an inlet water port connectible to a water supply for the room and an outlet water port connectible to the water closet.

A shutoff valve is positioned in the housing, as is an automated sensor. There is also a microcontroller coupled to the sensor and shutoff valve. When the assembly is positioned in the room (e.g. mounted to a supply pipe and also an outlet pipe to the toilet), and the sensor is supplied with power, the sensor is suitable to detect when a potential user is adjacent the water closet. If a potential user is detected the sensor will send an output signal to the microcontroller such that the microcontroller can open the shut-off valve (thereby permitting water to be supplied to the toilet).

In preferred forms the sensor is selected from the group consisting of proximity sensors and motion sensors, a battery is provided in the housing to supply power to at least the sensor, and there is a manual override to permit the water supply to the water closet to be shut off even if the sensor senses an adjacent human (e.g. for maintenance work).

The assembly can include a timer to shut off water supply to the water closet once a pre-determined time has elapsed after the assembly opens the shutoff valve (e.g. if the homeowners leave the building for several hours the water supply will automatically turn off even if the sensor for some reason still is indicating presence). Alternatively, the assembly can be designed so that after the sensor has signaled the presence of a potential user it will thereafter monitor for the absence of potential users. When that happens, the microcontroller will close the shutoff valve in response thereto.

The assembly is designed to be mounted in an inconspicuous location (e.g. slightly to the side of the lower tank, e.g. near where the user normally sees a manual shutoff valve). It is most preferably positioned so that the housing gives a sufficient view to the sensor so as to properly trigger the controls.

A single compact housing can completely shroud the sensor, the automated shutoff valve, and the power supply. Thus, there does not need to be any exposed wiring. The assembly can be pre-assembled at a factory so that an electrician is not needed to install the device on site. Moreover, the remaining connections are so straightforward that even a consumer that is relatively unskilled in plumbing installation techniques will be able to complete the installation.

These and still other advantages of the present invention will become apparent from the following description. In that description, reference is made to the accompanying drawings which form a part hereof, and in which there are shown preferred embodiments of the invention. Such embodiments do not represent the full scope of the invention, and reference is therefore made, to the claims herein for interpreting the full scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an assembly of the present invention which has been installed for use with a conventional toilet;

FIG. 2 is a schematic diagram showing the connections between the various components inside the assembly housing of FIG. 1; and

FIG. 3 is a flow chart demonstrating the operation of a microcontroller of the FIG. 1 assembly.

DETAILED DESCRIPTION OF THE INVENTION

An automatic shutoff valve and sensor assembly 10 is shown in FIGS. 1 and 2. The assembly 10 has a water supply shutoff valve 12 (e.g. such as a solenoid type valve such as the one depicted in U.S. Pat. No. 4,915,347, the disclosure of that patent being entirely incorporated by reference as if fully set forth herein). There is also a sensor 14 (such as an infrared proximity detector as described in U.S. Pat. No. 4,915,347).

A housing 16 has an inlet connection or port 18 linking to a supply line 22 from the room water supply 36. The housing also has an outlet connection or port 20 linked to an outlet line 24 that ultimately leads to a tank 25 of a toilet 26.

There can also be provided a power supply 28, preferably in the form of a battery, and a control board 30 in the form of a microcontroller. The microcontroller receives receiving inputs from the sensor 14 and sends outputs to the shutoff valve 12.

Battery 28 can be a replaceable battery, or can be rechargeable (e.g. via a solar cell, or using the power of the water to generate recharging power, or by other means). Alternatively, but not preferably, the system could be plugged into room power. In any event, regardless of the source of the power, the power source will power the sensor 14, the control board 30 and also preferably a valve actuator 32 linked to shutoff valve 12.

A manual override could be positioned upstream of the housing at a position comparable to that shown in U.S. Pat. No. 6,367,096. However, this would present a somewhat bulky and aesthetically unpleasant appearance.

Hence, it is preferred to also incorporate a manual override into the housing. For example, as shown in FIG. 1, one could place a button 34 on the top of the housing. Pressing the button would send an electrical signal to shut off the water for a defined period until the button is pressed again. This would permit maintenance work on the toilet even though the sensor will still be giving a signal that the shutoff valve should be in the open position.

Referring next to FIG. 3, there is schematically shown process 50 for operating the assembly. One starts with the shutoff valve closing off flow to the toilet. As noted in block 52, microcontroller 30, via sensor 14, then monitors the vicinity immediately surrounding the toilet for a potential user.

Once a person is detected by the sensor 14, as schematically illustrated by decision block 54, microcontroller 30 produces an output signal to energize the shutoff valve actuator 32, as schematically illustrated by block 56. Energizing the actuator 32 causes the actuator 32 to open the valve 12. Once valve 12 is open, water is supplied to the tank 25 of toilet 26 as needed.

For as long as a person is detected, along with a predetermined time afterwards (e.g. one minute), actuator 32 remains energized and shutoff valve 12 remains in the open position. Then, as shown in decision block 58, after a person is no longer sensed by sensor 14, microcontroller 30 de-energizes actuator 32 after the pre-determined length of time.

Valve 12 then returns to its closed position, shutting off the water supply to the toilet 26. At this point the process cycle is over and the process 50 returns to block 52 to monitor for the presence of another potential user.

As long as no potential user is sensed, the outlet line 24 to the toilet 26 is then isolated from water supply 36. Hence, if at that point the tank 25 cracks, the amount of water leaking out onto the surrounding floor will be limited to the volume of water present in a single fill of the tank 25. Furthermore, if water starts continuously running into the tank for any reason, such as if a flapper valve (not shown) is stuck open, valve 12 will then quite quickly prevent additional water from being wasted when no potential user is detected.

One may wish to provide protection against the sensors being tricked into believing that someone is present when they aren't (e.g. especially in public restrooms). For example, if a janitor places a waste basket in front of the sensor without thinking about the sensor, or if a vandal tapes over the sensor window in a public bathroom installation, the system may think that someone is always present, thereby defeating the system's protection.

Hence, one may want to include in the circuitry the capability of shutting off the supply if the sensors sense presence for an unusually long period (e.g. several hours), or alternatively provide an automated restart of the cycle after a specified period.

The assemblies of the present invention can be made and installed at low cost, are compact and thus aesthetically attractive, can be used without exposed wiring, and reduce the potential for water leaking and/or being wasted.

A variety of changes can be made to the preferred structures described above without departing from the spirit or scope of the invention. For example, although infrared proximity sensors are preferred for this application, other types of presence sensors can be used. Also, while a rectangular box with five walls (no rear wall) is a preferred form of housing, numerous other shapes for the housing could be used, with or without a back wall.

Hence, the claims should be looked to in order to judge the full scope of the invention and the invention is not to be deemed limited to just the preferred embodiments.

INDUSTRIAL APPLICABILITY

Disclosed are automatic shutoff valves useful with toilets. 

1. An automatic shutoff valve and sensor assembly suitable for use with a water closet positioned in a room, the assembly comprising: a housing mountable upstream of the water closet, the housing having an inlet water port connectible to a water supply for the room and an outlet water port connectible to the water closet; a shutoff valve positioned in the housing; an automated sensor positioned in the housing; and a microcontroller coupled to the sensor and shutoff valve; wherein if the assembly is positioned in the room, linked to a water supply for the room and the water closet, and supplied with electrical power, the sensor is suitable to detect when a potential user is adjacent the water closet, and if it does so detect an adjacent potential user, the sensor can send an output signal to the microcontroller such that the microcontroller can open the shutoff valve.
 2. The assembly as recited in claim 1, wherein the sensor is selected from the group consisting of proximity sensors and motion sensors.
 3. The assembly of claim 1, further comprising a battery suitable to supply power to the assembly.
 4. The assembly of claim 3, wherein the battery is linked to the sensor, the microcontroller, and the shutoff valve to supply power to all three.
 5. The assembly as recited in claim 1, further comprising a manual override mounted on the housing to permit the water supply to the water closet to be shut off even if the sensor is sensing an adjacent potential user of the water closet.
 6. The assembly as recited in claim 1, further comprising a timer to shut off water supply to the water closet once a pre-determined time has elapsed after the assembly opens the shutoff valve.
 7. The assembly as recited in claim 1, wherein after the sensor has signaled a presence of a potential user it can thereafter signal an absence of potential users, and when this occurs the microcontroller will send a signal to close the shutoff valve. 